A system, in which tomorrow morning's papers are downloaded from a host computer to a terminal at a set time (in the night), so that the user can read the morning papers when he gets up, is conventionally available as an example network system composed of the host computer and terminals connected to the host computer via communication lines, such as telephone lines and radio signals. According to this system, the user can receive the data he wishes to see from the host computer automatically at night by avoiding the use in a daytime when the communication lines are much busier.
Japanese Laid-open Patent Application No. 139747/1996 (Tokukaihei No. 8-139747) discloses an e-mail receiving system furnished with selection means for classifying received mails in accordance with keywords ranked according to importance and for selecting received mails in accordance with the keyword indexes. According to this system, urgent or important mails are selected with precedence to enable the user to check the contents thereof at his earliest convenience.
However, in any of the above systems, a relation between a memory capacity of each terminal and a total volume of mails (a total volume of incoming mails) from the host computer is not concerned particularly. Thus, when the latter is greater than the former, for example, the terminal can not receive all the mails from the host computer, and the user may not be able to receive urgent or important mails.
Thus, to receive urgent or important mails in a reliable manner, the user has to manage the terminal to always secure a memory capacity sufficient for a total volume of the coming mails. Thus, the conventional systems have a problem that the system management is very troublesome.